The invention relates to an airbag for a vehicle occupant restraint system.
On inflation of an airbag, it can be advantageous if the airbag at first does not move in the direction to the vehicle occupant but towards the side instead. There are already proposals for controlling the unfolding direction of the airbag, for instance by deflecting the incoming gas by means of a fabric part in the airbag, as is described in DE 296 09 706. In another proposal disclosed in DE 200 09 816, the mid-section of the front wall of the airbag is attached to the back wall by fastening means. When the airbag is inflated, the fastening means are destroyed by the pressure or by the temperature of the gas flowing in.
The object of the invention is to provide an airbag that reproducibly expands first in the direction of its side wall when it is inflated.
This is achieved in an airbag that comprises an airbag wall which has a front wall facing the occupant to be restrained, a back wall and a side wall. The front wall and the back wall are connected to each other by means of a detachable connection. This connection between the front wall and the back wall is severed by the unfolding of the side wall when the airbag is inflated. Since the front and back walls are connected to each other at the start of the inflation procedure, the side wall unfolds first. Only through the unfolding of the side wall is the connection severed, thus ensuring that, in any case, the airbag will first expand laterally.
Additional advantageous embodiments of the invention will be apparent from the subordinate claims.